2-Methylquinoline → 5,6,7,8-Tetrahydro-2-methylquinoline

Participants

Reaction Steps

A solution of quinaldine (available from Aldrich) (25 mL, 176 mmol) in trifluoroacetic acid (140 mL) was hydrogenated at 50 psi hydrogen in the presence of PtO2 (2.62 g, 11.5 mmol) for 1.5 h at rt. (This method was conducted in accordance with Bell, T. W. et. al. J. Am. Chem. Soc. 2002 124, 14092 incorporated herein by reference). The mixture was filtered through filter paper, diluted with water and crushed ice, and made basic by the addition of solid NaOH until the mixture was pH>10. The aqueous layer was extracted with hexane. The pooled organic layers were washed with water and dried over MgSO4. The mixture was filtered and evaporated to give 2-methyl-5,6,7,8-tetrahydro-quinoline (Intermediate 200A1) as a clear, yellow oil ˜25 g (98%).

Provenance & Evidence